9th class Physics unit 6 MCQs
chapter 6 MCQs 9th Class Physics
Work and Energy:
1. The work done will be zero when the angle between the force and the distance is:
a. 900
b. 450
c. 1800
d. 600
2. If the direction of the force is perpendicular to thedirection of motion of the body, then work done will be:
a. Zero
b. Maximum
c. Minimum
d. None of these
3. The SI unit of work is:
a. Watt
b. Newton
c. Pascal
d. Joule
4. If the velocity of a body becomes double, then its kinetic energy will:
a. Become four times
b. Remain the same
c. Become half
d. Become Double
5. The kinetic energy of a body of mass 2 kg is 25 J. Its speed is:
a. 25 ms-1
b. 5 ms-1
c. 50 ms-1
d. 12.5 ms-1
6. Kinetic energy is directly proportional to the ………velocity of a body:
a. Three Times
b. Square
c. Four times
d. Two Times
7. If the velocity of a body becomes three times greater,then kinetic energy will be:
a. Four times
b. Three Times
c. Six Times
d. Nine Times
8. The energy possessed by a body by virtue of its motion is called
a. Kinetic energy
b. Nuclear energy
c. Potential energy
d. Chemical energy
9. The work done in lifting a brick of mass 2 kg through a height of 5 m above ground will be
a. 50 j
b. 2.5 j
c. 100 j
d. 10 j
10. The energy in the stretched bow is:
a. Heat energy
b. Elastic potential energy
c. Sound energy
d. Kinetic energy
11. Hammer raised up has energy
a. Sound energy
b. Potential energy
c. Heat energy
d. Kinetic energy
12. Which one of the following converts light energy into electrical energy?
a. Photocell
b. Electric bulb
c. Electric cell
d. Electric generator
13. When a body is lifted through a height h, the work done on it appears in the form of its:
a. Elastic potential energy
b. Kinetic energy
c. Geothermal energy
d. Potential energy
14. The energy stored in coal is
a. Chemical energy
b. Heat energy
c. Nuclear energy
d. Kinetic energy
15. The energy stored in dam water is:
a. Kinetic energy
b. Electric energy
c. Thermal energy
d. Potential energy
16. ……… device converts light energy into electrical energy:
a. Photocell
b. Electric bulb
c. Electric cell
d. Electric generator
17. In Einstein’s mass-energy equation, c is the:
a. Speed of electron
b. Speed of sound
c. Speed of Earth
d. Speed of light
18. There is a hot molten part, deep in the Earth called:
a. Mixture
b. Lava
c. Plasma
d. Magma
19. The source to produce pollution free electricity is:
a. Wind turbine
b. Coal
c. Radioactivity
d. Oil
20. Rate of doing work is called:
a. Power
b. Energy
c. Momentum
d. Torque
21. Power is equal to:
a. W 2 / t
b. W x t
c. W / t
d. W / t 2
22. 10 joules work is done by a machine in 5 sec, its power will be:
a. 25 W
b. 2 W
c. 50 w
d. 10 W
23. One horse power is equal to:
a. 1000 W
b. 764 W
c. 1100 W
d. 746 W
24. 1 MW is equal to:
a. 10 6 W
b. 10 2 W
c. 10 8 W
d. 10 4 W
25. One kilo joule is equal to:
a. 109 W
b. 103 W
c. 10-3 W
d. 106 W
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